Waterproof seam and method of making same



Aug. 27, 1929. G, w, BLAIR 1,725,749

WATERPROOF SEAM AND METHOD OF MAKING SAME Filed D90. 15, 1924 e t; Gegzye- 715310327 Patented Aug. 27, 1929.

UNITED STATES 1,725,749 PATENT OFFICE.

GEORGE W. BLAIR. OF MISHAWAKA, INDIANA, ASSIQNOR T MISHAWAKA RUBBER &WOOLEN MANUFACTURING COMPANY, OF MISHAWAKA, INDIANA, A CORPORA- rron orINDIANA.

WATERPROQF SEAMI AND METHOD OF MAKING SAME.

Application filed December 15, 1924. Serial No. 755,830.

My invention has reference to the waterproofing of stitched seams and isparticularly useful in connection with articles of footwear. 7

a It is a common practice to make heavy shoes of leather or part leatherand part rub ber, waterproof so that they keep out the moisture in wetweather and when used in wet places. It has been found,'however, that 10the stitched seams in shoes of this character oftentimes are notentirely waterproof, as thewater and moisture works its'way between thelapped edges and through the openings through -whichthe stitches arepassed. It is the purpose of this invention to avoid this leakage infootwear by providing a method and means for thoroughly sealing thelapped joint and the openings through which the stitches are passed.

On the drawings:

Fig. 1 is a side View of a shoe embodying my invention;

Fig. 2 is an enlarged sectional View on. the line 22 of Fig. 1; and Fig.3 is a section verv much enlarged,

taken on the line 3'3 of Fig. 1.

Referring to the drawings, the reference numeral 1 indicates the footportion of a shoe, said portion being made of rubber in so theparticular shoe which is illustrated, and preferably provided with afabric lining 2 on the inner side. The upper 3 of the shoe is made ofleather and consists of quarters which may be unitary or sewed togetheralong their rear edges, as shown, with a tape 4 overlying the joint, andthese quarters have their front edges secured to a tongue 5, which isusually of a bellows form.

It is customary in shoes of this character, to secure theoupper 3 to thefoot portion 1' of the shoe by a number-of lines of stitches 5, a tape 7of fabric being usually interposed between the two parts so that the oilfrom the leather will not injuriously affect the &5 rubber of the footportion 1. The stitching ofthe upper to the foot portion does not alwaysdraw the parts together tight enough to form a waterproof joint, and asthe stitching is made with rather coarse thread so as to insure asubstantial connection, it sometimes happens that the openings throughwhich the threads are passed, are not closed '0. sufficiently tight toprevent water leaking tfierethrough. Moreover the water or moisturewhich works its way into the semen ppenings'docs not dry out readily andhas an 111]l11l011S effect on the thread. To avoid these disadvantages Iemploy a tape 8 of leather upper 3 as indicated at 9 in Fig. 3

and protrudes slightly from the outer ends of the stitch openings. Thishas a further effect of preserving the threads as the sealing of theopenings in the leather upper 3 prevents the moisture from penetratinginto the stitch openings where it naturally dries more slowly than onthe exterior and afiords a greater opportunity therefore for rotting ofthethreads.

It is to be understood that this waterproofing may be employed at anypoints where stitching or other fastening of the parts together affordsopenings through which leakage may occur. In practice a strip 10 of softrubber is interposed for sealing purposes between the strip 4': at theback of the shoe and thejupper 3, and this rubber scaling is alsoapplied between the lower portion of the tongue 5 where it is Wconnected with the foot portion 1 and also where the tongue is connectedto the lower portion of the upper 3 so as to insure a perfect waterproofconnection betweenthe foot portion 1 and the upper portion of the shoe.

While l have shown and described my in- .vention in a preferred form, llam aware that various changes and modifications may be made withoutdeparting from the principles of my invention, the scope of which is tobe determined by the appended claims.

I claim as my invention:

1. The methodof connecting a layer of leather and a layer of rubber toform a waterproof joint which comprises interposing a strip of softerrubber between the layer of leather and the layer of rubber andintcrposing a strip of fabric between the strip of soft rubber and thelayer of rubber and then applying a plurality'of rows of stitchesthrough the layers of leatherand rubber and the strips of soft rubberand fabric and thereby compressing the soft 'rubber and forcing portionsthereof into the stitch openings of the layer of leather.

2. In a shoe, a foot portion, an upper having its lower edge overlappingthe top of the foot portion, a thick soft rubber sealing element betweenthe overlapped portions of said upper and said foot portion, and apluralit of substantially parallel rows of stitc es extending throughthe overlapped upperandfoot portion and also through the soft rubber andholding said parts under compression, the outer ends of thestitchopenings being exposed at the exterior of the shoe portions ofsaid rubber sealing element being extruded by thecompression into andclosing the ends of the stitch openings.

3. A shoe seam, comprisin overlapped shoe upper members, a thick so trubber sealing element between the overlapped shoe members, and aplurality of substantially parallel rows of stitches extending throughthe overlapped shoe members and the rubber sealing element and holdingsaid parts under compression, the outer ends oflthe stitchopenings beingexposed at the exterior of the shoe, portions of said rubber sealingelement being extruded by the compression into and closing the ends ofthe stitch openings.

4. The method of forming a stitched waterproof shoe upper seam whereinthe outer ends of the stitch-openings are exposed at the exterior of theshoe, which consists in interposing a soft rubber sealing elementbetween overlapped shoe members, and stitching a plurality ofsubstantially parallel rows ofstitches through theoverlapped shoemembersand the sealing element and drawing the stitches tight and therebyextrudingportions of the sealing element into and closing the ends ofthe stitch openings,

GEORGE w BLAIR,

